Research Progress and Prospects of Magnetic Nanomaterials

Nanomaterials are one of the research and development hotspots in the field of cutting-edge new materials,and also an important strategic emerging industry.Magnetic nanomaterials have broad application prospects in fields such as chemical engineering,new materials,electronic information,and biomedicine.This article introduces the application progress and preparation methods of magnetic nanomaterials,and puts forward suggestions for further optimizing the preparation process of magnetic nanomaterials and developing new magnetic materials with better performance.

New Nano Polymer Materials for Composite Exterior-Wall Coatings

A triethylenetetramine epoxy mixture was synthesized through the reaction of a low-molecular-weight liquid epoxy resin with triethylenetetramine(TETA).Then triethyltetramine(TETA)was injected dropwise into a pro-pylene glycol methyl ether(PM)solution for chain extension reaction.A hydrophilic andflexible polyether seg-ment was introduced into the hardener molecule.The effects of TETA/DGEPG,reaction temperature and reaction time on the epoxy conversion of polyethylene glycol diglycidyl ether(DGEPG)were studied.In addition,several alternate strategies to add epoxy resin to the high-speed dispersion machine and synthesize MEA DGEBA adduct(without catalyst and with bisphenol A diglycidyl ether epoxy resin)were compared.It was found that the higher the molecular weight of triethylenetetramine,the longer the chain segment of the surface active molecule.When the equivalence ratio of amine hydrogen and epoxy group is low,the stability of lotion is good.When the ratio of amine hydrogen to epoxy group is large,the content of triethylenetetramine is small.The main objective of this study is the provision of new data and knowledge for the development of new materials in the coating and electronic industry.

抗菌PP/Rnano-ZnO复合材料的制备及性能研究

以棒状纳米氧化锌(Rnano-ZnO)为抗菌剂、聚丙烯(PP)为基材,采用熔融共混法在双螺杆挤出机中制备了抗菌PP/Rnano-ZnO复合材料。测试了复合材料的抗菌性能,通过DSC法研究了抗菌PP/Rnano-ZnO复合材料中Rnano-ZnO质量分数对结晶性能的影响,采用SEM分析了复合材料冲击断面的微观形貌,采用万能电子拉伸机测试了复合材料的力学性能。结果表明,抗菌PP/Rnano-ZnO复合材料中随着Rnano-ZnO的加入,结晶温度提高了1.81℃,相对结晶度提高了5.03%,冲击强度提高了47.83%,拉伸强度提高了20.96%和断裂伸长率提高了4790%;当抗菌PP/Rnano-ZnO复合材料中Rnano-ZnO质量分数为6.0%时,其力学性能、对大肠杆菌和金黄色葡萄球菌的抗菌效果最佳。

Vascular endothelial growth factor protein and gene delivery by novel nanomaterials for promoting liver regeneration after partial hepatectomy

Partial hepatectomy(PH)can lead to severe complications,including liver failure,due to the low regenerative capacity of the remaining liver,especially after extensive hepatectomy.Liver sinusoidal endothelial cells(LSECs),whose proliferation occurs more slowly and later than hepatocytes after PH,compose the lining of the hepatic sinusoids,which are the smallest blood vessels in the liver.Vascular endothelial growth factor(VEGF),secreted by hepatocytes,promotes LSEC proliferation.Supplementation of exogenous VEGF after hepatectomy also increases the number of LSECs in the remaining liver,thus promoting the reestablishment of the hepatic sinusoids and accelerating liver regeneration.At present,some shortcomings exist in the methods of supplementing exogenous VEGF,such as a low drug concentration in the liver and the reaching of other organs.Moreover,VEGF should be administered multiple times and in large doses because of its short half-life.This review summarized the most recent findings on liver regeneration and new strategies for the localized delivery VEGF in the liver.

The Microparticles SiOx Loaded on PAN-C Nanofiber as Three-Dimensional Anode Material for High-Performance Lithium-Ion Batteries

Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing Si-based anode materials,the C/SiOx structure is made up of PAN-C,a 3D carbon substance,and SiOx load-ing steadily on PAN-C.The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure.When employed as lithium-ion batteries(LIBs)anode materials,C/SiOx-1%composites were discovered to have an extremely high lithium storage capacity and good cycle per-formance.At a current density of 100 mA/g,its reversible capacity remained at 761 mA/h after 50 charge-dis-charge cycles and at 670 mA/h after 200 cycles.The C/SiOx-1%composite aerogel is a particularly intriguing anode candidate for high-performance LIBs due to these appealing qualities.

Nano-SiO_(2)改性水泥净浆结石体力学特性试验研究

岩土领域复杂的工程地质环境和工程地质灾害对注浆材料的性能提出了更高的要求。利用电液伺服岩石真三轴试验机开展了普通425水泥结石体、添加纳米二氧化硅浆液结石体的单轴压缩试验。试验结果表明,添加纳米二氧化硅后,浆液结石体力学性能得到明显提升,且纳米二氧化硅含量在3%时效果最好。与普通水泥浆液结石体相比,添加3%纳米二氧化硅的浆液结石体单轴抗压强度增加了56.3%,弹性模量增加了29.2%。试验结果可以为复杂地质环境下的工程项目注浆设计和施工提供参考。

Synthesis of porous nano/micro structured LiFePO_4/C cathode materials for lithium-ion batteries by spray-drying method

In order to enhance electrochemical properties of LiFePO4 （LFP） cathode materials, spherical porous nano/micro structured LFP/C cathode materials were synthesized by spray drying, followed by calcination. The results show that the spherical precursors with the sizes of 0.5-5 μm can be completely converted to LFP/C when the calcination temperature is higher than 500 ℃. The LFP/C microspheres obtained at calcination temperature of 700 ℃ are composed of numerous particles with sizes of -20 nm, and have well-developed interconnected pore structure and large specific surface area of 28.77 mE/g. The specific discharge capacities of the LFP/C obtained at 700 ℃ are 162.43, 154.35 and 144.03 mA.h/g at 0.5C, 1C and 2C, respectively. Meanwhile, the capacity retentions can reach up to 100% after 50 cycles. The improved electrochemical properties of the materials are ascribed to a small Li＋ diffusion resistance and special structure of LFP/C microspheres.

Preparation of Nano-porous Materials(Ⅰ) by Polymerization of Amphiphile Self-assemblies

The polymerization of amphiphilic self assemblies is a promising method to synthesize nano structured materials with novel properties. These materials have many attractive features for their application in biomedical area and materials science, such as catalysis, separation, surface modification, and therapeutics areas. A general review on the polymerization of lipids and surfactant self assemblies to amphiphilic self assemblies is given in this paper with 49 references. The polymerization and the subsequently resulted structure of lipids in different morphologies are summarized. The polymerization of polymerizable surfactants(surfmers) in emulsion and liquid crystalline phases are also discussed. The potential application of new nano porous materials is briefly described.

Construction and Properties of Structure-and Size-controlled Micro/Nano-energetic Materials

The recent research progress of structure- and size-controlled micro/nano-energetic materials is reviewed, which properties are fundamentally different from those of their corresponding bulk materials. The development of the construction strategies for achieving zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) micro/nanostructures from energetic molecules is introduced. Also, an overview of the unique properties induced by micro/nanostructures and size effects is provided. Special emphasis is focused on the size-dependent properties that are different from those of the conventional micro-sized energetic materials, such as thermal decomposition, sensitivity, combustion and detonation, and compaction behaviors. A conclusion and our view of the future development of micro/nano-energetic materials and devices are given.

Synthesis and Characterization of Storage Energy Materials Prepared from Nano-crystalline Cellulose/Polyethylene Glycol

This paper gives a brief report of the synthesis of a new kind of solid-solid phase change materials （SSPCMs）, nano-crystalline cellulose/polyethylene glycol （NCC/PEG）. These PCMs have very high ability for energy storage, and their enthalpies reach 103.8 J/g. They are composed of two parts, PEG as functional branches for energy storage, and NCC as skeleton. The flexible polymer PEG was grafted onto the surface of rigid powder of NCC by covalent bonds. The results of DSC, FT-IR were briefly introduced, and some comments were also given.

Agglomerating Growth of One-Dimensional Carbon Nano-Materials Synthesized from Ethanol Flames

One-dimensional carbon nano-materials （ODCNMs） synthesized from ethanol flames exhibit various agglomerated morphologies, such as ＂chrysanthemum-like＂, ＂hairball-like＂ or ＂orange-peel-like＂, ＂vertically aligned＂ and ＂wrinkling-pileup＂. The present work studied the agglomerating process and the growth mechanism by using scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. It is thought that the size and distribution of the catalyst particles produced from pretreatment of the substrates play a key role during the formation of agglomerations. It is expected that the steady growth of ODCNMs in flames will be improved through the preparation of the catalysts.

纳米N-A降黏剂的制备及性能评价

针对普通纳米降黏剂对特稠油降黏效果差、洗油效率低等问题,制备了纳米N-A降黏剂,采用FTIR,TEM等方法表征了降黏剂的微观结构,考察了降黏剂的降黏效果、界面张力以及洗油效率。实验结果表明,纳米N-A降黏剂组成为:50%(w)纳米二氧化硅溶胶+40%(w)分散剂EB-1+4.2%(w)表面修饰剂+5.8%(w)增效剂。该降黏剂分散性能良好,粒径分布在20~60 nm之间,在降黏剂含量为1%(w)、油水质量比为7∶3、200℃,矿化度为0,8829.26 mg/L条件下老化48 h,特稠油降黏后黏度分别为6280,7213 mPa·s,降黏率分别达到83.77%,81.36%,降黏性能保持率分别为96.80%,95.39%。50℃下静置90 d后降黏性能保持率大于90%,可降低油水界面张力至0.076 mN/m,乳化液滴最大粒径9.5μm,洗油效率为30.9%,相对普通降黏剂,驱油效率提高22.3百分点。

介孔La_(1-x)Sr_(x)MnO_(3)催化剂的COK-12纳米浇铸法制备

钙钛矿型催化剂在汽车尾气净化方面具有良好的应用潜力。本文以表面活性剂P123为软模板剂,廉价的硅酸钠为硅源,在近中性条件下制备了介孔材料COK-12。并以此为基础,以对二甲苯为扩容剂对COK-12进行改性,得到了大孔径、有序的介孔材料。随后以改性介孔材料为模板剂,采用纳米浇铸法结合溶胶-凝胶法制备了介孔La_(0.8)Sr_(0.2)MnO_(3)催化剂。结果显示,在550℃下合成的催化剂具有较大的比表面积(72.11 m^(2)/g),表面Mn^(4+)/Mn^(3+)和O_(ads)/O_(lat)摩尔比最高。此外,样品的CO催化性能测试转化表明,550℃下合成的样品具有最好的催化活性和优秀的高温稳定性,其特征温度T_(50)和T_(90)分别为180和218℃。

Nano-CB改性发泡木塑复合材料性能研究

为提升木塑复合材料(WPC)的功能性,将纳米导电炭黑(Nano-CB)作为抗静电和阻燃填料,通过模压法制备阻燃抗静电型发泡木塑复合材料(FWPC)。探究Nano-CB对FWPC性能的影响,分析其作用机理。结果表明,Nano-CB较佳的加入量为8%,此时,FWPC的静曲强度、弹性模量、拉伸强度和冲击强度分别为33.38,2739,15.59 MPa和4.49 kJ/m^(2),表面电阻率和体积电阻率对数值均为8,抗静电性能显著提高,氧指数为21.8%,最大热释放速率和平均热释放速率分别为345.92,143.34 kW/m^(2),阻燃性能小幅增强。SEM分析表明:未加Nano-CB时,FWPC燃烧后表面炭层较薄,结构蓬松,存在大量的孔洞,加入改性Nano-CB后,FWPC燃烧炭层连续致密,表面未见气孔。

Research on Infrared Emissivity and Laser Reflectivity of Sn_(1−x)Er_(x)O_(2)Micro/Nanofibers Based on First-Principles

Sn_(1−x)Er_(x)O_(2)(x=0%,8%,16%,24%)micro/nanofibers were prepared by electrospinning combined with heat treatment using erbium nitrate,stannous chloride and polyvinylpyrrolidone(PVP)as raw materials.The target products were characterized by thermogravimetric analyzer,X-ray diffrotometer,fourier transform infrared spectrometer,scanning electron microscope,spectrophotometer and infrared emissivity tester,and the effects of Er^(3+)doping on its infrared and laser emissivity were studied.At the same time,the Sn_(1−x)Er_(x)O_(2)(x=0%,16%)doping models were constructed based on the first principles of density functional theory,and the related optoelectronic properties such as their energy band structure,density of states,reflectivity and dielectric constant were analyzed,and further explained the mechanism of Er^(3+)doping on SnO_(2)infrared emissivity and laser absorption from the point of electronic structure.The results showed that after calcination at 600℃,single rutile type SnO_(2)was formed,and the crystal structure was not changed by doping Er^(3+).The calcined products showed good fiber morphology,and the average fiber diameter was 402 nm.The infrared emissivity and resistivity of the samples both decreased first and then increased with the increase of Er^(3+)doping amount.When x=16%,the infrared emis-sivity of the sample was at least 0.71;and Er^(3+)doping can effectively reduce the reflectivity of SnO_(2)at 1.06μm and 1.55μm,when x=16%,its reflectivity at 1.06μm and 1.55μm are 50.5%and 40%,respectively,when x=24%,the reflectivity at 1.06μm and 1.55μm wavelengths are 47.3%and 42.1%,respectively.At the same time,the change of carrier concentration and electron transition before and after Er^(3+)doping were described by first-principle calculation,and the regulation mechanism of infrared emissivity and laser reflectivity was explained.This study provides a certain experimental and theoretical basis for the development of a single-type,light-weight and easily prepared infrared and laser compatible-stealth material.

Thermodynamic analysis of growth of ternary Ⅲ-Ⅴ semiconductor materials by molecular-beam epitaxy

Thermodynamic models for molecular-beam epitaxy（MBE） growth of ternary Ⅲ-Ⅴ semiconductor materials are proposed.These models are in agreement with our experimental materials InGaP/GaAs and InGaAs/InP,and reported GaAsP/GaAs and InAsP/InP in thermodynamic growth.The lattice strain energy △G and thermal decomposition sensitive to growth temperature are demonstrated in the models simultaneously.△G is the function of the alloy composition,which is affected by flux ratio and growth temperature directly.The calculation results reveal that flux ratio and growth temperature mainly influence the growth process.Thermodynamic model of quaternary InGaAsP/GaAs semiconductor material is discussed also.

2D multifunctional devices:from material preparation to device fabrication and neuromorphic applications

Neuromorphic computing systems,which mimic the operation of neurons and synapses in the human brain,are seen as an appealing next-generation computing method due to their strong and efficient computing abilities.Two-dimensional (2D) materials with dangling bond-free surfaces and atomic-level thicknesses have emerged as promising candidates for neuromorphic computing hardware.As a result,2D neuromorphic devices may provide an ideal platform for developing multifunctional neuromorphic applications.Here,we review the recent neuromorphic devices based on 2D material and their multifunctional applications.The synthesis and next micro–nano fabrication methods of 2D materials and their heterostructures are first introduced.The recent advances of neuromorphic 2D devices are discussed in detail using different operating principles.More importantly,we present a review of emerging multifunctional neuromorphic applications,including neuromorphic visual,auditory,tactile,and nociceptive systems based on 2D devices.In the end,we discuss the problems and methods for 2D neuromorphic device developments in the future.This paper will give insights into designing 2D neuromorphic devices and applying them to the future neuromorphic systems.

Thrust characteristics of nano-carbon/Al/oxygenated salt nanothermites for micro-energetic applications

Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.

Carbon dioxide catalytic conversion to nano carbon material on the iron–nickel catalysts using CVD-IP method

The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide （CO2）, which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to ex- plore efficient and sustainable approaches for the carbon-neutral pathway of CO2 utilization and recycling. In our recent works with this context, we developed successfully a novel ＂chemical vapor deposition integrated process （CVD-IP）＂ technology to converting robustly CO2 into the value-added solid-form carbon materials, The monometallic FeNi0-Al2O3 （FNi0） and bimetallic FeNix-Al2O3 （FNi2, FNi4, FNi8 and FNi20） samples were synthesized and effective for this new approach. The catalyst labeled FNi8 gave the better performance, exhibited the single pass solid carbon yield of 30%. These results illustrated alternative promising cases for the CO2 capture utilization storage （CCUS）, by means of the CO2 catalytic conversion into the solid-form nano carbon materials.

鲤疱疹病毒二型(CyHV-Ⅱ)疫苗研究进展

鲤疱疹病毒Ⅱ型(Cyprinid herpesvirus Ⅱ,CyHV-Ⅱ)对任何发育时期的金鱼、鲫鱼及其杂交品种均具有感染能力,能够引起金鱼疱疹病(goldfish haematopoietic necrosis, GFHN),是一种传染性强且死亡率极高的疫病,给我国金鱼和鲫鱼养殖业造成巨大经济损失,鱼用疫苗的研发是预防和治疗该疫病最有效的办法。综述了CyHV-Ⅱ灭活疫苗、亚单位疫苗、核酸疫苗、活载体疫苗和纳米递送疫苗的研究进展,并对鱼用疫苗纳米材料的应用前景进行了探讨,以期为金鱼疱疹病害防治和鱼用疫苗研究提供新技术方法和新思路策略。